Question

( x -3) + ( x - 2 ) + ( x -1 ) +...+10 + 11 =11

Answer 1

(x - 3) + (x - 2) + (x - 1) + ... + 10 + 11 = 11

(x - 3) + (x - 2) + (x - 1) + ... + 10 = 0

(x - 3) + (x - 2) + (x - 1) + 55 = 0

(x - 3) + (x - 2) + (x - 1) = -55

3x - (3 + 2 + 1) = -55

3x - 6 = -55

3x = -49

x = -49/3

Answer 2

Ta có: (x-3)+(x-2)+(x-1)+x+...+10+11=11

\(\Leftrightarrow x-3+x-2+x-1+x+1+2+3+4+5+6+7+8+9+10+11=11\)

\(\Leftrightarrow4x+60=11\)

\(\Leftrightarrow4x=-49\)

\(\Leftrightarrow x=\frac{-49}{4}\)(ktm)

Vậy: \(x\in\varnothing\)